We are using EDUCON tempalate. https://www.joomshaper.com/downloads/template/educon

When I tried to upgrade Joomla 6. So I disabled the backwards compatibility plugin, after that frontend crashes.

Error message: "Sorry, there was a problem we could not recover from." The server returned a "500 - Whoops, looks like something went wrong."

how to resolve this issue and upgrade Joomla 6 properly?